Process of purifying pine-oil, pine-tar oil, and wood-tar oil.



O. P. PELLNITZ.

PROCESS OF PURIFYING PINE OIL, PINE TAR OIL, AND WOOD TAR OIL.

APPLICATION FILED JUNE 6, 1907.

910,146. Patented Jan.19,1909.

zymww 47 5M4 OTTO PAUL PELLNITZ', OF DELMENHORST, GERMANY.

PROCESS OF PURIFYING PINE-OIL PINE-TAR OIL, AND WOOD-TAR OIL.

Specification of Letters Patent.

I Patented Jan. 19, 1909.

Application filed June 6, 1907. Serial No. 377,548.

" To all whom 'it may concern:

Be it known that I, Orro PAUL PELLNITZ, a subj ect of the Emperor ofGermany, resident of Delmenhorst, Oldenburg, Germany,Hasbergerstrasse,have invented a new and useful Process of PurifyingPine-Oil, Pine- Tar Oil, and Wood-Tar Oil.

Pine-oil, pine-tar-oil and 'wood-tar-oil become changed, in consequenceof the high temperature required for the dry distillation of the wood,by oxidations, condensations, polymerizations andso on, and polluted bythe pyro-compounds, empyreumatic resins and tarry ingredients which alsohave an unfavorable influence on the smell and color of the said oils.

Pine oils are made from the very resinous wood of the root of the pineby dry distillation and by succeeding rectification (comp. H. Bliicher,Auslcunftsbuch fit?" die Chemische lndust'rz e, III. J ahrgang,\Vittenberg, verlag von Herros und Ziemsen, page 7 95). Pine-tar-oilsand woodtar-oils are made from the pine-tar and Wood-tar respectively(comp. the above mentioned book, page 340).

The object of this process is on the one hand to reduce by means ofzinc-dust the oils oxidized through the high temperature in the courseof the dry distillation of the wood and, on the other, to eliminate thepyrocompounds, empyreumatic resins and tarry ingredients aszinc-compounds. If these impurities are not completely removed, therewill show itself a yellow or yellowbrown color during the transformationof the turpentine-oils into resins. The disadvantage is avoided bywashing the oil according to the present process. The acids contained inthe raw-oil are bound by the zinc dust and eliminated. It is thereforenot necessary to wash the raw-oils with lyes for removing the acidsbefore the treatment with zinc-dust.

This process has the advantage over other known processes of beingsimpler and cheaper to carry out and the loss caused by the purificationbeing smaller. By the purifying-processes now known the raw-oils receivea darker color by the, treatment, so that at least two distil lationsare required to make them colorless, while according to the presentprocess the raw oi1s assume, in

consequence of the treatment, a much lighter color, so that the productremains permanently colorless. after one distillation; the pine oils aremoreover distinguished by their pure turpentine smell.

In the accompanying drawing the device in connection with a condenserasused for this process is shown in a side elevation, partially insection.

In the practical carrying out of the process 1,000 kg. of pine-tar-oilare heated with 10 kg. of zinc-dust, for two hours, in a closedreceptacle or still as a, up to about 100 C. During the heating processwater contained in the oil evaporates and forces oil with it. Thereforethe'closed receptacle is connected with a condenser b in which thevaporized parts of water and oil are con 'dcnsed and flow back againinto the receptacle through the cohnecting tube (1. The chamber 6,provided with a steam coil is, is filled with water of 60 to 70 C. Thesoil vaporized and not mixed with water passes through the tube 6 intothe cooling device 0. The cooling water is supplied through the pipe 7and then rises successively through c, g, and the vessel surrounding theworm in b to pass oif by it. through the vessel 0 to pass therefrom by apipe 2' in the .lower right hand portion. After the cooling, the oil iscarefully drawn off from the zinc-compounds at the bottom of the device0 into a washing-apparatus (not shown) provided with a stirring-gear andwashed with warm, soft or slightly alkaline water until the water, whenlye containing about thirty per cent. natrium hy-- droxid is added, doesno longer turn yellow. Hereupon the oil is distilled by direct steam orover an open fire. The pine-oils are distilled by direct steam, whilethe wood-taroils are preferably distilled over an open fire, as thisdistillation is cheaper than the distillation by steam and its highertemper-.

ature does not cause any change of constitution of the ingredientsof thewood tar-oils, what would be the case with pine-oils.

nets of the dry distillation of pine-wood as pine-oils, pine-tar-oilsand wood-tar-oils consisting essentially of terpens are supposed to bepurified. The most preclous elements of these oils are not saturatedcom- The pipe e passes,

In the process vegetable oils, 2'. e. prodbinations and are not affectednor altered by paratus provided with a stirring-gear, by 10 thepurification according to this process. Washing 1t With Waterand bydistilling the C aim oil, substantially as s" ecified.

The process of purifying pine-oil, pine- In Witness whereo I havehereunto set tar-oil and wood-tar-oil by heating the same my hand in thepresence of two Witnesses. With zinc-dust for two hours in a; closed're-& OTTO PAUL PELLNITZ. ceptacle provided with a condenser up toWitnesses: about 100 C. by cooling thereafter theoil, FERDINAND REIOH,by drawing off the same into a washing ap FRIEDRICH VON Ess.

